1. Field of the Invention
This invention relates to fuel tank for vehicles and more particularly, to a molded "plastic" fuel tank or "fuel cell" for racing vehicles and a mold for shaping the fuel cell. A primary feature of the fuel cell and mold detailed herein is the provision of a fuel cell having a molded wedge in the bottom thereof, which molded wedge extends from one side of the fuel cell to the other in angular relationship between the end portions. This wedge design facilitates the isolation of small quantities of fuel in a confined space between the molded wedge and one end of the fuel cell for more efficient fuel pick-up when the fuel cell is almost empty. The angle is created in the molded wedge by utilizing a two-piece split mold having a bottom section fitted with a wedge blade slot for receiving a removable wedge insert blade which defines the shape of the molded wedge in the fuel cell. In a preferred embodiment, the wedge insert blade is secured in the wedge blade slot, a granulated plastic material such as polyethylene is introduced along with a polymerization catalyst into the bottom section of the two-piece mold, the mold is closed by seating the top section on the bottom section and the top section is attached to a conventional rotating apparatus capable of rotating the mold simultaneously on two axes. The mold is then located in a furnace and heated while the rotating apparatus is operated, to melt the plastic powder, initiate the polymerization reaction and line the inside of the two-piece mold with the chosen plastic material in a desired thickness and consistency. The fuel cell is then removed from the mold by removing the top segment of the mold and the wedge insert blade.
2. Description of the Prior Art
One of the problems realized at a relatively early date in the racing of automobiles on oval tracks was that of designing a fuel tank or cell system which is capable of removing the last few ounces of fuel from the tank while the racing car is operating at high speeds. This problem is intensified by centrifugal force which operates on the fuel and causes the fuel to "pool" at the outside end of the tank as the racing car travels in an oval configuration on the track in a counterclockwise direction. Since the fuel pick-up mechanism is normally located in the center of the tank, when the tank is almost empty, the fuel is displaced from the pick-up mechanism by centrifugal force and the fuel pick-up mechanism is unable to remove all of the fuel from the tank. The problem has been partially eliminated by orienting the fuel pick-up mechanism at the juncture between the side and bottom of the tank, to retrieve more fuel when the tank is almost empty. However, due to the size of the tank, this fuel is normally distributed across the inside peripheral bottom and side portions of the tank in a thin layer, thereby further rendering complete emptying of the tank impossible. A modern solution to the problem is the construction of metal tanks having a molded wedge built therein, which wedge extends from one side of the tank to the other in angular orientation toward one end of the tank. The wedge is typically angled to the right, or outside, as the racing car and tank are viewed from the rear, in order to facilitate the flow of fuel over the top of the wedge by centrifugal force, where the fuel is trapped in a small space located between the right hand, or outside end of the tank and the angled underside of the wedge itself. The fuel pick-up mechanism is oriented to extend into this small compartment to facilitate retrieval of small quantities of fuel which remain in the tank during a race. Accordingly, the molded wedge serves as a collection device for isolating and collecting residual quantities of fuel for more efficient pick-up to the carburetor or fuel injection system of the racing car when the tank is almost empty.
A problem which is realized in the construction of metal fuel tanks of this design is the expense of such construction, which requires extensive fabrication by hand to create the metal wedge compartment in the interior of the tank and facilitate the desired collection of residual quantities of fuel. A cheaper design has long been sought and other materials of construction have been envisioned for the construction of lighter and less expensive fuel tanks, or cells from plastic or alternative materials which are impervious and non-reactive to methanol and other fuel blends used in modern racing cars.
Accordingly, it is an object of this invention to provide a new and improved molded fuel tank or cell and mold therefore, which molded fuel cell is characterized by a container of selected size having a molded wedge provided in the bottom thereof near the right hand, or outside end, as the fuel cell is viewed from the rear when oriented in a racing car located in racing position on an oval track and traveling in a counterclockwise direction, in order to facilitate the collection and pooling of fuel in a small area defined by the molded wedge and the right hand end of the fuel cell.
Another object of the invention is to provide a new and improved fuel tank, container or cell for racing cars, which fuel is molded from a plastic material such as polyethylene, in non-exclusive particular, and includes a wedge portion molded in angular relationship in the bottom near one end of the fuel cell, for trapping and collecting residual quantities of fuel during a race and facilitating the removal of substantially all of the fuel from the fuel cell by operation of conventional fuel pick-up devices.
Yet another object of this invention is to provide a new and improved molded thermosetting fuel cell for use in racing vehicles, which fuel cell is characterized by a plastic, wedge-shaped barrier molded in the bottom of the fuel cell between the sides thereof and oriented in angular relationship near a collection end of the fuel cell, for collecting fuel in a confined space or compartment between the wedge and the collection end, in order to facilitate more efficiently retrieving the fuel from the fuel cell using conventional fuel pick-up apparatus.
A still further object of this invention is to provide a split mold for molding a plastic fuel cell having an angled molded wedge in the bottom thereof, which mold is further characterized by a top segment and a bottom segment, the bottom segment further including a tapered wedge blade slot and a wedge insert blade designed to removably engage the wedge blade slot, for shaping the molded wedge in the fuel cell.
Still another object of the invention is to provide a new and improved split mold for molding a plastic fuel cell for containing fuel for racing cars, which mold is characterized by a top segment and a bottom segment that are joined at matched, flat flanged faces thereof and which bottom segment further includes a wedge blade slot provided in angular relationship in opposite sides thereof near one end of the mold and a wedge insert blade shaped for insertion in the wedge blade slot, in order to facilitate molding of the fuel cell by operation of a conventional rotating apparatus about dual axes during application of heat to the mold.